CN1622550A - Real-time communications system of high communications quality and media terminal apparatus - Google Patents
Real-time communications system of high communications quality and media terminal apparatus Download PDFInfo
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- CN1622550A CN1622550A CNA2004100958587A CN200410095858A CN1622550A CN 1622550 A CN1622550 A CN 1622550A CN A2004100958587 A CNA2004100958587 A CN A2004100958587A CN 200410095858 A CN200410095858 A CN 200410095858A CN 1622550 A CN1622550 A CN 1622550A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/10—Architectures or entities
- H04L65/102—Gateways
- H04L65/1023—Media gateways
- H04L65/1026—Media gateways at the edge
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/10—Architectures or entities
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- H04L65/1036—Signalling gateways at the edge
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/1066—Session management
- H04L65/1101—Session protocols
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/75—Media network packet handling
- H04L65/762—Media network packet handling at the source
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/75—Media network packet handling
- H04L65/764—Media network packet handling at the destination
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M7/00—Arrangements for interconnection between switching centres
- H04M7/006—Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP), including next generation networks with a packet-switched transport layer
- H04M7/0072—Speech codec negotiation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M7/00—Arrangements for interconnection between switching centres
- H04M7/12—Arrangements for interconnection between switching centres for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal
- H04M7/1205—Arrangements for interconnection between switching centres for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks
- H04M7/1245—Arrangements for interconnection between switching centres for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks where a network other than PSTN/ISDN interconnects two PSTN/ISDN networks
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Abstract
A VoIP system has plural CPE units connected to an IP network as parties to be connected with each other. Each CPE unit is composed of a VoIP-IF circuit and an audio codec circuit. The VoIP-IF circuit executes at least one of the coding process to the first audio frequency signal and the restoration process to the media information to transmit the media information generated by the process to the party connected and restore the first audio frequency signal from the media information supplied from the party connected to output it. The audio codec circuit performs at least one of the sending of the received music data to the party and the conversion of the music data supplied from the party into the second audio frequency signal.
Description
Technical field
The present invention relates to the real-time communication system and the media terminal apparatus of high communication quality.The invention particularly relates to the real-time communication system that preferably is applicable to based on the Speech Communication of VoIP (IP speech agreement) technology.The present invention also relates to media terminal apparatus according to MIDI (musical instrument digital interface) standard deal with data.
Background technology
Musical instrument according to MIDI (musical instrument digital interface) standard and similar standard can be exported the MIDI data.The MIDI data are not the waveforms of sound itself, but by will be such as pitch, the duration of a sound, several audio parameters of tone convert numerical data to and obtain.Therefore can be with data size much smaller than performance content from the data description electronic musical instrument of the direct coding of waveform own.
Use midi standard to make a kind of teaching method become possibility, the student will play the MIDI storage obtained storage medium from his/her electronic musical instrument, and by mail or mail service storage medium is sent to his/her and be positioned at long-range director, thereby will play this director of context notification, can play by instruction of papil in being based on this performance content director.
In addition, the analog telephony transmission sound or the speech that may use ordinary public telephone switching network (PSTN) to provide.Therefore, use analog telephony to realize Karaoke, vocal music and/or instrument playing course are possible.
Usually, the bandwidth of the voice signal by analog telephony transmission is limited to very narrow 300-3,400 hertz bandwidth.Transmit without any problem in this bandwidth common acoustic.But because limited bandwidth, vocal music, the non-constant of communication quality of Karaoke and instrument lesson.Particularly, for vocal music, the Karaoke and the speech and the voice signal of musical instrument, be lower than 300 hertz extremely important with the frequency content that is higher than 3400 hertz.But the use analog telephony, these important component are deleted and can not be transmitted.Therefore handle in the communication of the outer frequency signal of voice band and comprise many problems.
And, when storing the storage medium of MIDI data, not the problem of the bandwidth of requirement by the mail service transmission, but the problem of non real-time.Therefore, promote the communication between trainee and the director, and realize that effectively music lesson is very difficult.
Summary of the invention
The objective of the invention is to reduce above-mentioned shortcoming, a kind of real-time communication system and media terminal apparatus of the higher communication quality of maintenance of novelty is provided, between the user, set up in real time intercommunication mutually whereby.
According to the present invention, the real-time communication system based on communication protocol on a kind of network is provided, wherein, the audio frequency media information relevant with first audio signal is inserted in the data of the protocol data relevant with this communication protocol, and the employed first and second media termination unit of user are one of them kind intercommunication mutually by sending and receiving on real-time basis.This system comprises: information conversion circuit, be used for realizing operating below at least one: produce audio frequency media information and recover first audio signal by coding based on the audio frequency media information that provides from second terminal unit based on first audio signal that receives from first terminal unit in real time communication; And interface circuit, be used to realize at least one following operation: receive the first music data that provide from the second media termination unit with a kind of data format, the first music data be converted to second audio signal and receive second music data from the first media termination unit to send this second music data.
According to the present invention, the first and second media termination unit all are connected to network to intercom mutually as the connection side.In the cataloged procedure by first audio signal and the recovery process of media information at least one, the information conversion circuit of each media termination unit sends to the connection side with the media information that this process produces, with first audio signal output that will recover from the media information that the connection side provides, the interface circuit of terminal unit is carried out at least one following operation: the music data that receives is sent to the connection side and will be converted to second audio signal from connection side's music data.By exporting sound, can greatly promote the intercommunication mutually between the user with first and second transmission of audio signals characteristics from media termination unit separately.
And, according to the present invention, the media terminal apparatus that is interconnected to network based on communication protocol is provided, is used for the audio frequency media information relevant with first audio signal is inserted into the data of the protocol data relevant, and on real-time basis, communicates by letter with its connection side with this communication protocol.This equipment comprises: information conversion circuit, be used for realizing operating below at least one: produce audio frequency media information and recover first audio signal by coding based on the audio frequency media information that provides from described connection side based on first audio signal that receives from its near-end in real time communication; Interface circuit, be used to realize at least one following operation: receive the first music data that provide from described connection side with a kind of data format, the first music data be converted to second audio signal and receive second music data from near-end to send this second music data.
According to the present invention, at least one in the cataloged procedure by first audio signal and the recovery process of media information, the media information that the information conversion circuit transmission is produced by this process, and first audio signal recovered from the media information that is provided of output.Be converted at least one operation of second audio signal by the music data that received of output with music data, the sound that interface circuit has the first and second transmission of audio signals characteristics from separately media termination unit output.Therefore, can improve communication quality, and by using multiple information can set up in real time intercommunication mutually.
Description of drawings
Consider following detailed description about accompanying drawing, purpose of the present invention and feature will be clearer and more definite, wherein:
Fig. 1 is the illustrative configurations block diagram according to the preferred embodiment of VoIP system of the present invention, and wherein real-time communication system is applied to this VoIP system;
Fig. 2 is the schematic block diagram of middle CPE unit embodiment illustrated in fig. 1;
Shown in Figure 3 is illustrative configurations according to the optional embodiment of VoIP system of the present invention, and wherein real-time communication system is applied to this VoIP system;
Fig. 4 is the illustrative configurations block diagram of the CPE unit of middle user U1 use embodiment illustrated in fig. 1;
Fig. 5 is the illustrative configurations block diagram of the CPE unit that user U2 uses among Fig. 1;
Fig. 6, similar Fig. 3 illustrates the illustrative configurations according to another optional embodiment of VoIP system of the present invention, wherein real-time communication system is applied to this VoIP system;
Fig. 7, similar Fig. 3 still illustrates some illustrative configurations to another optional embodiment of multiple spot form according to VoIP system of the present invention, wherein real-time communication system is applied to this VoIP system;
Fig. 8, similar Fig. 3 illustrates the illustrative configurations according to the further embodiment of VoIP system of the present invention, wherein real-time communication system is applied to this VoIP system;
Fig. 9 is that explanation is used for the illustrative configurations block diagram that the network according to the further optional embodiment of VoIP system of the present invention connects, and wherein real-time communication system is applied to this VoIP system;
Figure 10, similar Fig. 1, shown in block diagram illustrating be used for the illustrative configurations that the Experimental Network according to another optional embodiment of VoIP system of the present invention connects, wherein real-time communication system is applied to this VoIP system;
Embodiment
Hereinafter, with reference to the embodiment of accompanying drawing detailed description according to real-time communication system of the present invention.Example embodiment is devoted to real-time communication system is applied to according to VoIP system 10 of the present invention.Accompanying drawing and explanation are omitted and are not directly related to element and the part of understanding invention.
As shown in Figure 1, VoIP system 10 comprises CPE (client's residential equipment) unit 12 and 14 as media terminal apparatus, modulator- demodulator 16 and 18, and microphone 20 and ear speaker device 22 and 24 and musical instrument 26 connect as figure.Modulator- demodulator 16 and 18 is connected to IP (Internet protocol) network by tie-in line 28 and 30.
The VoIP system 10 of present embodiment is applied to music lesson, sets up intercommunication mutually by Speech Communication, sends and receive the MIDI data.The VoIP system 10 of present embodiment comprises 2 subsystems: the subsystem that to be used for a user be student U1 is used for the subsystem that another user is director U2.2 subsystems can comprise identical structural element.Especially, CPE unit 12 and 14, modulator- demodulator 16 and 18, ear speaker device 22 and 24 is all corresponding to be provided in each side.Therefore, need not be to the repetition of identical explanation, below only explanation be used for the structural element of user U1.
Synchronizing function is with IP bag 40 and 42 mutually synchronization mutually.H.323, calling order is advised according to ITU-T (ITU Telecommunication Standardization Sector's door) and/or SIP (session initiation protocol) etc. set up call out after, send the IP bag 40 that carries voice data.Therefore, the IP bag 42 that carries music performance data also can preferably wrap 40 synchronized transmissions with IP.
In call control program, communication controler 34 is fit to send to be called out and sends ring, so the response of user U2 off-hook allows the transmission of IP bag 40 afterwards and allows the transmission of IP bag 42 in succession.In addition, VoIP system 10 also is fit to allow other users certainly, and promptly director U2 makes a phone call or sends to call out and give a user, i.e. student U1.Hereinafter, signal marks with the Reference numeral on its place line.
VoIP-IF circuit 36 provides and so-called voip gateway identical functions.The speech that user U1 sends is collected by the microphone 22A of ear speaker device 22, is encoded to voice data then in VoIP-IF circuit 36.Therefore, voice data is included in definite zone of IP bag 40, and sends to IP network 32 by communication controler 34 and modulator-demodulator 16.When a user U1 heard the speech of another user U2, the voice data string routine was opposite with said procedure.
Especially, the sound that the microphone 24A of the ear speaker device 24 of user U2 end collects is encoded, 14 send the IP bag 44 that comprises the voice data that is produced from the CPE unit then.So IP bag 44 orders are by modulator-demodulator 18, IP network 32 and modulator-demodulator 16 send to the VoIP-IF circuit 36 of CPE unit 12.VoIP-IF circuit 36 takes out voice data and decoding, and the loud speaker 22B by ear speaker device 22 exports decoded data.Now, user U1 can hear its connection side's sound.
In this situation, encoder that is used for encoding and the decoder that is used to decode all use the audio codec of the above-mentioned VoIP-IF of placing circuit 36 to realize.In this situation, audio codec is fit to encoding and decoding in the analog telephone frequency band.
Performance sampled voice and coding that 38 pairs of microphones of audio codec circuit 20 are collected, as shown in Figure 1, its sample frequency is higher than the audio codec in the above-mentioned VoIP-IF circuit 36.The codec circuit 38 then coding such performance data that will produce is put into IP bag 42, and send this bag.Such performance data is the Wave data that sound 46 is played in representative.
From the component of example embodiment, user U1 does not hear the sound that another user U2 plays.Therefore, 38 in audio codec circuit needs encoding device, and need not decoding device.But if desired, audio codec circuit 38 also can provide decoding device.In this situation, show that the user is that example or the example that director U2 plays is effective.
And present embodiment is so constructed: voice data is by 36 transmission of VoIP-IF circuit, and such performance data is by 38 transmission of audio codec circuit.But, also can will play sound as the voice data part, use 36 transmission of VoIP-IF circuit.In the later case, the characteristic of VoIP-IF circuit 36 can change to has sizable bandwidth, and it is much larger than the bandwidth of analog telephony, i.e. 300-3,400 hertz.For example, according to the ITU-T suggestion G.722, bandwidth can be 50-7,000 hertz.Broadband connections can be transmitted the voice data that is lower than 300 hertz and is higher than 3,400 hertz.Therefore, can use the performance sound of the structural element transmission user U1 identical with transmission user U1 speech.In addition, communication controler 34 needn't possess synchronizing function.
Broadband connections is also very favourable for improving communication quality.The pronunciation of words of certain language, for example English may comprise being higher than 3,400 hertz frequency content.When this high frequency band can not be transmitted, the transmission of Japanese speech signal relatively, the normal transmission of this speech signal can be interfered slightly.By broadband connections, can improve this phenomenon and effect thereof greatly.Especially, when at least one was spoken English among user U1 and the U2, broadband connections was more favourable.
Alternatively, system is fit to allow user U1 to select transmission method: will play sound and partly use wideband transmit as voice data, maybe will play sound as the such performance data transmission that is independent of voice data.
Turn to Fig. 1 now, modulator-demodulator 16 has line terminal equipment to stop tie-in line 28.Now, usually use various broadband services such as ADSL (asynchronous digital subscriber line) etc. as tie-in line 28 and 30.When tie-in line 28 is ADSL, use ADSL Modem certainly.In addition, when Optical Fiber Transmission was used for tie-in line 28, the working medium transducer was as optical terminus equipment.Clearly, tie-in line 30 can variety classes with tie-in line 28.In the embodiment shown in fig. 1, CPE unit 12 and modulator-demodulator 16 are independent structures elements.But modulator-demodulator can be installed in the CPE unit 12.And modulator-demodulator also can comprise routing device.
Microphone 20 and ear speaker device 22 are the user interface facilities that are connected to user U1.Microphone 20 and ear speaker device 22 are connected to modulator-demodulator 16 by CPE unit 12.Ear speaker device 22 is the equipment that comprises microphone 22A and loud speaker 22B, and microphone 22A collects sound and converts thereof into the corresponding signal of telecommunication.
For example, when the musical instrument sound that user self of output plays in the music lesson listened for another user, user U1 can be worn over ear speaker device 22 on the head, communicates by letter with another user U2.The microphone 22A of ear speaker device 22 collects the speech of user U1, and the audio codec with CPE unit 12 is encoded into audio data forms with it then, and data are included in the IP bag 40, sends to connection side's modulator-demodulator 18 by IP network 32.
The performance sound 46 of musical instrument 26 output user U1.Microphone 22A collects and plays sound 46, and the analog signal of obtaining is offered CPE unit 12.CPE unit 12,, to analog signal sampling and coding and is put into IP with coded data and is wrapped 42 with the sample frequency of the audio codec that is higher than analog telephony by audio codec circuit 38.IP bag 42 offers IP network 32 from CPE unit 12, is transferred to the modulator-demodulator 18 of another user side then by IP network 32.Microphone 20 is provided in this configuration, and therefore, except the musical instrument of MIDI type, other any musical instruments all can use.Therefore, user U1 can freely use any kind musical instrument common or electronics, keyboard instrument for example, piano, Chinese lute etc.
When musical instrument is when having the electronic musical instrument of analog signal output, CPE unit 12 can provide the input end of analog signal that connects analog signal output (not shown) and CPE unit 12 to replace microphone 20, therefore, exportable midi standard media data is as the back explanation.
The operation of VoIP system 10 will be described below.User U1 places microphone 20 near the musical instrument 26, and after putting on ear speaker device 22 on the head, he is preceptorial telephone number and its conversation by importing another user U2.In order to import desirable telephone number, can preferably provide some suitable user interface.Can use such as telephone set or the webpage on display device as user interface.
Dialing was prepared when this webpage wished to receive music lesson for user U1, and it comprises the abbreviation of using such as " U2 ", the specific guidance person's of his/her name and telephone number representative information.In CPE unit 12, the network gateway software that is fit to show the dialing webpage is installed preferably.Network gateway is a kind of web browser, and is except the software dial feature is provided, identical with common web browser.
When using network gateway, require to be connected to CPE unit 12 with display device with such as the sensing equipment of mouse, requirement will provide the network server apparatus of dialing webpage to place IP network 32.In this case, user U1 can dial user U2 with the operation of simplifying, and for example represents desirable called party's icon by sensing, and clicks his/her mouse.
When user U1 input called party's telephone number begins calling order, call out in the response of the called party U2 of CPE unit 14 ends off-hook, and on head, put on ear speaker device 24.Now, by the real-time Speech Communication between VoIP communication permission user U1 and the U2.Set up Speech Communication by transmission IP bag 40 and 44 on IP network 32.
In Speech Communication carried out, calling party U1 played his/her musical instrument 26, and microphone 20 is collected and played sound 46.So IP bag 42 comprises the such performance data that obtains from the performance sound 46 of CPE unit 12, and is transferred to called party U2.
Certainly, speech transmissions sound intermediate frequency data are to transmit on the basis in real time, and do not retransmit control.But in the application of such performance data bag and packets of audio data independent transmission, the IP bag 42 that comprises such performance data can transmit on the basis of the non real-time transmission with the control of retransmitting.For non real-time transmission, it is preferred retransmitting control, if any packet loss takes place on the IP network 32, can preferably duplicate fully and play sound 46 and do not have interruption.But the intercommunication mutually between user U1 and the U2 gets a promotion simultaneously with tight the carrying out of communicating by letter of performance and voice data.Therefore, preferably when real-time capacity is more important, on the real-time Transmission basis of not retransmitting control, send IP bag 42.
In addition, system is fit to allow user U1 or U2 suitably to select transport-type to wrap 42 with transmission IP from real-time and non real-time transmission.This optional transport-type is provided, and VoIP system 10 can be based on the situation that packet loss takes place, and any one transport-type is used in decision adaptively.
For the VoIP system 10 with the control of retransmitting, when packet loss took place, the IP bag 42 identical with lost package retransmitted in the CPE unit 12 of transmitting terminal.The arrival of the IP bag of retransmitting 42 is waited in the CPE unit 14 of destination, duplicates and export performance sound 46 then.In this situation, do not keep the most accurate real-time capacity.But as mentioned above, the real-time capacity of the repeating transmission of VoIP system 10 control is much larger than the method that sends the storage medium of store M IDI data by mail.Therefore, though this is a kind of non-realtime traffic, we can say to have kept being close to satisfied real-time capacity.
Under any circumstance, when another user is that director U2 listens performance sound, when therefrom finding slight change and providing suitable the guidance, a user is that student U1 can respond this guidance and play his/her musical instrument again in the mode of trickle modification, thereby realizes the remote music course.Even user U1 and U2 position wide apart, music lesson are also almost finished with long-time fixing aspectant course the samely.For example, when user U1 lived in his/her country, when user U2 lived in foreign country, this course was highly beneficial.And, the language of user U1 and U2 not simultaneously, install machinery interpreting equipment at least one CPE unit 12 and 14 can be finished real time communication by machine translation.
Use above-mentioned VoIP system 10, various music lesson services can be provided and need not move, thereby be easy to provide immediately multiple service from a plurality of preceptorial low tuition fees in the world.The student is too young and/or the director is too old and be difficult for when mobile, and present embodiment can more effectively provide service.Therefore,, promote the intercommunication mutually on the real-time basis, can realize favourable remote music course by improving the multiple information of communication quality and utilization such as audio frequency and such performance data.
The optional embodiment of VoIP system 10 will be described below, and real-time communication system of the present invention is applied to this VoIP system.After this, for avoiding repetition, the difference with previous embodiment only is described to unnecessary explanation.Same Reference numeral is represented same structural element, wherein omits repeat specification.As shown in Figure 3, the VoIP system among the optional embodiment has USB (the USB)-midi interface 48 between MIDI cable CPE unit 12 and the musical instrument 26.
USB-MIDI interface 48 provide the MIDI data also-string translation function and the data that are converted of output, the MIDI data offer input connector by 5 pin DIN (Deutsche industry norm (DIN)) cables from musical instrument 26.MIDI is connected to the agreement of synthesizer with synthesizer interconnection or with computer, for example, can realize that by this agreement speed is 31, the transmission of 250bps.The data of transmitting on the MIDI cable are not the sampled datas of similar PCM (pulse code modulation), but comprise tone information and music at interval.By the MIDI data of the command format explanation determined with the MIDI agreement, rather than represent the such performance data of the performance sound waveform of musical instrument 26, transmission information.MIDI data command normally length is the message of 1,2 or 3 bytes.
As shown in Figure 4, the CPE unit 12 of VoIP system 10 comprises MIDI-interface (IF) circuit 50, has replaced the audio codec circuit 38 that comprises in the previous embodiment.The function of MIDI-IF circuit 50 is to compile the IP bag 42 that comprises the MIDI data, and with its transmission.In this embodiment, the information of representative performance sound is transmitted with the MIDI data mode.Therefore, reduced the requirement to broadband connections, 36 transmission of EXAMPLE V oIP-IF circuit are lower than 300 hertz of audio bandwidth signals that are higher than 3,400 hertz as previously mentioned.And the MIDI data of handling in optional embodiment are numerical datas, even the normal replication of the performance sound of CPE unit 14 ends is not allowed one mistake mixing or abandoned.This makes that the repeating transmission control of IP bag is preferred.
Data of handling among the embodiment more as shown in figs. 1 and 3, about onesize data, the numerical data of handling in optional embodiment can be represented speech or voice signal in considerable time.Therefore, if the repeating transmission of IP bag 42 has a fixed response time, user U2 also can ignore it, thinks the audio frequency output of user U2 end and duplicates the time delay of playing between the voice output.
For example, CPE shown in Figure 5 unit 14, suitable reception comprises the IP bag 42 of MIDI data and comprises the IP bag 40 of voice data.CPE shown in Figure 5 unit 14 comprises sound source module 52 and mixer 54 and the structural element identical with Fig. 4.Sound source module 52 is so-called MIDI sound source modules, and the function of duplicating the performance sound of representing the MIDI data is provided, and the MIDI data are obtained from the IP bag 42 that MIDI-IF circuit 50 receives.Sound source module 52 comprises the ROM (read-only memory) of the information of storage such as tone color.According to MIDI data read stored information to duplicate and to export performance sound.
The function that the reproduced output signal of sound mixes is played in the decoded data that mixer 54 has a representative of consumer U1 speech that VoIP-IF circuit 36 is provided and the representative that sound source module 52 provides, thereby output audio mixing result listens to user U2.Mixer 54 also offers VoIP-IF circuit 36 with the speech of user U2.VoIP-IF circuit 36 produces the IP bag 40 that comprises user U2 voice signal, sends it to CPE unit 12.
The same with the system of previous embodiment, the VoIP system 10 that native system uses has been realized in real time intercommunication mutually and effective remote music course.By the repeating transmission control to the IP bag 42 that comprises the MIDI data, the system 10 of present embodiment offers user U2 with higher-quality performance sound and listens.
To describe the another kind of optional embodiment of VoIP system 10 below, real-time communication system of the present invention is applied to this VoIP system.Present embodiment has that his/her plays sound as example from user U2 transmission, and uses the feature of auditory information and visual information, therefore makes intercommunication mutually more healthy and stronger.Shown in Figure 6 is VoIP system 10 according to present embodiment.
On the other hand, another user, or director U2 can play the musical instrument 26 identical with user U1 as example.Representative is transferred to the CPE unit 12 of user U1 from the MIDI data of the synthetic sound of his/her performance.By MIDI-IF circuit 50, sound source module 52 and mixer 54, CPE unit 12 offers ear speaker device 22 with the MIDI data.Now, user U1 can listen example or example to play.
In this embodiment, can use non real-time transmission to comprise the IP bag of view data with transmission with the control of retransmitting.But, preferably also use the real-time Transmission of not having the control of retransmitting.And, the image data transmission from the student to director's direction has only been described among this embodiment.But be not limited in above-mentioned direction, the bidirectional picture transmission also is possible, and wherein video is played example and can be transferred to the student.In this situation, VoIP system 10 can add USB camera 56 and display 58 at user U2 and U1 front end respectively.By transmitting above-mentioned video information, student and the more approaching aspectant music lesson of preceptorial mutual understanding degree.
Still describe the another kind of optional embodiment of VoIP system 10 below, real-time communication system of the present invention is applied to this VoIP system.In this embodiment, many-to-one music lesson can be finished by a plurality of students and a director.In this situation, user U3 is the same with user U1, is the student that the user is the music lesson that provides of director U2 is provided.Therefore, the structural element of user U3 front end and user U1 are identical.
Shown in Figure 7, on IP network 32, be equipped with audio mixing (MIX) server 60 according to the VoIP system 10 of present embodiment.Audio mixing (MIX) server 60 comprises repeat circuit 61 and such as the miscellaneous equipment of sound source module and mixer, does not offer some clarification among Fig. 7.Therefore, CPE unit 12 and 14 can comprise structural element same as shown in Figure 4.But MIDI-IF circuit 50 may only comprise transmission equipment.Therefore, for VoIP system 10, the repeat circuit 61 of audio mixing server 60 mixes the performance result of student U1 and U3 shoegaze 26, and mixed content is transferred to director U2, and will send to student U1 and U3 respectively from voice signal and the performance example that director U2 receives.This performance sound that makes director U2 hear seems that student U1 and U3 play physically independent musical instrument 26 with their both hands.
In this embodiment, two students use the keyboard instrument with musical instrument 26 same standards, but needless to say, they also can use the musical instrument of various criterion.In an application, user U2 can hear 3 or more students' performance sound simultaneously, for example, he/or she can make one group of student play symphony.Audio mixing server 60 can offer each student with audio mixing output and listen.Equally, system is fit to mix these students' speech and plays sound, thereby sets up communication simultaneously between the student who participates in same course.For individual training, system also be fit to realize between director and each student and communicating by letter between the student.Therefore, VoIP system 10 not only can be used for man-to-man music lesson, also can be used for many-to-one music lesson.
To describe the further optional embodiment of VoIP system 10 below, real-time communication system of the present invention is applied to this VoIP system.VoIP system 10 shown in Figure 8 is corresponding to the system that has been equipped with data conversion server 62 on IP network 32 shown in Figure 3.Data conversion server 62 comprises data converting circuit 62A, it is fit to and will the 12 MIDI data of transmitting that are included in IP bag 42 be converted to voice data from the CPE unit, promptly play the Wave data of sound, these data are identical with the voice data of VoIP-IF circuit 36 codings.Server 62 also comprises repeat circuit 62B, and it is fit to transfer of data or is relayed to the CPE unit and non-translation data.By repeat circuit 62B, the IP bag that data conversion server 62 will comprise converting audio data is transferred to CPE unit 14.
By using this configuration, the CPE unit 14 of user U2 can be incompatible with midi standard, and do not require the MIDI sound source module, thereby make configuration simplify.
When tie-in line 28 and 30 is asymmetric transfer rate circuit such as ADSL, its upload and download rate is asymmetric mutually, thus its to upload the bandwidth ratio download bandwidth narrow, by the data conversion server on the IP network 32 62, the MIDI data are converted to voice data, make size of data increase.But the data increase is at down direction, and therefore asymmetric speed tie-in line has been mated in conversion well, even more effective.Reason is, on the one hand, uploading direction, data by tie-in line 28 when CPE unit 12 is transferred to data conversion server 62, desired transmission size is littler, and on the other hand, in download directions, when data conversion server 62 was transferred to CPE unit 14, desired transmission size was bigger by tie-in line 30 for data.
When using data conversion server 62 or audio mixing server 60, the server position may increase jumping figure, thereby causes some shortcoming, and for example the real time communication time delay increases and the communication quality instability.Therefore, should carefully select the position of server.
And, among Fig. 3, between musical instrument 26 and CPE unit 12, disposed the USB-MIDI interface as interface equipment.The function of interface equipment can provide in musical instrument 26 or CPE unit 12.Further, clearly the use of USB is not absolutely necessary.For example in the above description, ear speaker device 22 can replace with hands-free phone equipment.
As shown in Figure 9, between user front end, may there be a network rather than an IP network 32.Usually, when the student of inhabitation wide apart communicates by letter with the director in the music lesson, use usually multiple network and, or replace IP network 32.For example, a kind of as in the multiple network, ISP network or " AS " they are available.
As shown in Figure 9, when the user U1 that lives in Japan intercoms in music lesson mutually with the user U2 that lives in the U.S., user U1 is by Japanese ISP network ISP1 64, thereby IP network 32 is communicated by letter with another user U2 with American I SP network 66 and accepted music lesson.Especially, disposing the VoIP system 10 with structure shown in Figure 10 is in order to steadily improve communication quality.By a simple communication experiment, Japanese user U1 is through ISP1 64, and TIR1 network 68 is communicated by letter with another user U2 with special line 70, has confirmed the configuration of VoIP system 10.TIR1 network 68 is one of main providers.
The TIR1 network is a kind of ISP network, by a large-scale main American I SP operation.As everyone knows, the internet is the set of ISP network, based on the routing information kind of carrying out route, sets up staging hierarchy between the ISP network.The TIR1 network is the top ISP network that is positioned at staging hierarchy, safeguards routing information, is routed to any ISP network on the internet by these information, even to any autonomous networks AS.
If the user is interconnected to ISP network rather than TIR1 network 68, the IP bag that some has the address that can not locate suitable routing information finds suitable routing information thereby may be relayed to different ISP networks.System configuration as shown in figure 10, a student can receive a plurality of preceptorial real time remote music lessons in the world, and a director goes up real-time course can for a plurality of students in the world.
In addition, the present invention not only can be applicable to instrument lesson, also can be applicable to vocal music and Karaoke course.Use the IP agreement among the foregoing example embodiment, but the agreement that is used for the OSI Reference Model network layer not to be defined in the IP agreement.For example, can use Internetwork Packet Exchange.
And example embodiment of the present invention realizes by hardware configuration.But also can realize the present invention by software arrangements.Nearly all function that realizes with example, in hardware can realize that vice versa with software arrangements.
In above-mentioned configuration, CPE unit 12 and 14 is connected to IP network 32 respectively as calling party and callee.CPE unit 12 and 14 VoIP-IF circuit 36 are carried out at least one following process: to the cataloged procedure of first audio signal with to the recovery process of media information, thereby the media information that this process is produced is transferred to its connection side, with will revert to first audio signal from the media information that its connection side receives, with output signal.Audio codec 38 is carried out at least one following operation: send the music data that is received and arrive its connection side and will be converted to second audio signal from the music data that its connection side receives.Each CPE unit 12 and 14 therefore output has from the sound of the transmission characteristic of first and second audio signals combination, thereby has promoted the intercommunication mutually between the user.Real time communication is finished with the simplification configuration that improves communication quality.
In an application, at least one CPE unit is that its VoIP-IF circuit 36 only comprises the transmission of music data and the CPE unit 14 of receiving function, and VoIP system 10 may be equipped with change server 62 on IP network 32.The data converting circuit 62A of change server 62 is converted to music data the audio signal of midi standard, (otherwise realizing) by CPE unit 14, thereby repeat circuit 62B will be inserted into the audio signal of midi standard or associating conversion with it such as the music data that receives from CPE unit 12, and the data after will inserting are relayed to and do not have the CPE of interface circuit unit 14.Simplified the configuration of CPE unit 14 and whole system like this.
In real time communication, VoIP-IF circuit 36 produces the image encoded media information based on the picture signal that receives from USB camera 56, or the image encoded media information is reverted to original image signal as realizing circuit.Therefore, can obtain video information on real-time basis, display image also improves communication quality.
The applied CPE unit 12 and 14 according to the present invention, VoIP-IF circuit 36 is carried out at least one following process: to the cataloged procedure of first audio signal, with recovery process to media information, thereby with the media information of this process generation and first audio signal output that recovers from the media information that is provided.Medium coding-decoding circuit 38 is carried out at least one following operation: the music data that output is received and music data is converted to second audio signal, thus produce the sound that has from from the transmission characteristic of first and second audio signals combination of separately CPE unit.Therefore,, can improve communication quality, promote real-time mutual understanding by using multiple information.
The full disclosure of the Japanese patent application No. 2003-400080 of application on November 28th, 2003 comprises prospectus, claims, and accompanying drawing and summary, its full content merges as a reference at this.
Embodiment has described the present invention with reference to specific example, but it is not limited to present embodiment.Be appreciated that when not departing from scope and spirit of the present invention those skilled in the art can change or revise present embodiment.
Claims (16)
1. the real-time communication system on the network based on communication protocol, wherein relevant with first audio signal audio frequency media information is inserted in the data of the agreement relevant with this communication protocol, and the employed first and second media termination unit of user are on real-time basis, by send with receive at least a intercommunication mutually, this system comprises:
Information conversion circuit, be used for below real time communication is carried out at least one, operating: produce audio frequency media information and recover first audio signal by coding based on the audio frequency media information that provides from second terminal unit based on first audio signal that receives from first terminal unit; And
Interface circuit, be used to carry out at least one following operation: receive the first music data that provide from the second media termination unit with a kind of data format, the first music data be converted to second audio signal and receive second music data to send this second music data from the first media termination unit.
2. system according to claim 1 further is included in the audio mixing server that provides on the network, wherein
Described audio mixing server comprises first repeat circuit, being used for will be based on the data of the agreement relevant with this communication protocol from the transmission of the first and second media termination unit, be relayed to the 3rd media termination unit, data with sending from the 3rd media termination unit based on the agreement relevant with this communication protocol be relayed to the first and second media termination unit.
3. system according to claim 1, wherein the described interface circuit of at least one media termination unit only has the transmission and the receiving function of music data,
The described system disposition that provides on network has change server, is used for converting music data to second audio signal and relaying,
Described change server comprises:
Change-over circuit is used for based on the agreement relevant with this communication protocol, and the first music data of taking out from the data that the second media termination unit sends are converted to the media information of second audio frequency; And
Second repeat circuit be used for the media information of second audio frequency is inserted into the data of this agreement, and the data that will insert is relayed to the media termination unit that does not possess described interface circuit.
4. system according to claim 2, wherein the described interface circuit of at least one media termination unit only has the transmission and the receiving function of music data,
The described system disposition that provides on network has change server, is used for converting music data to second audio signal and relaying,
Described change server comprises:
Change-over circuit is used for based on the agreement relevant with this communication protocol, and the first music data of taking out from the data that the second media termination unit sends are converted to the media information of second audio frequency; And
Second repeat circuit be used for the media information of second audio frequency is inserted into the data of this agreement, and the data that will insert is relayed to a media termination unit that does not possess described interface circuit.
5. system according to claim 1, wherein, below described information conversion circuit is carried out in real time communication in the operation any one: produce image media information and from the image media information that is encoded, recover original picture signal by coding based on the picture signal that receives from the first media termination unit.
6. system according to claim 2, wherein, below described information conversion circuit is carried out in real time communication in the operation any one: produce image media information and from the image media information that is encoded, recover original picture signal by coding based on the picture signal that receives from the first media termination unit.
7. system according to claim 3, wherein, below described information conversion circuit is carried out in real time communication in the operation any one: produce image media information and recover original picture signal by coding from the image media information that is encoded based on the picture signal that receives from the first media termination unit.
8. system according to claim 1, wherein said media termination unit comprises mixer, be used for by first audio signal recovering from audio frequency media information to obtain with mix by second audio signal of obtaining from music data conversion.
9. system according to claim 4, wherein said media termination unit comprises mixer, be used for by first audio signal recovering from audio frequency media information to obtain with mix by second audio signal of obtaining from music data conversion.
10. system according to claim 7, wherein said media termination unit comprises mixer, be used for by first audio signal recovering from audio frequency media information to obtain with mix by second audio signal of obtaining from music data conversion.
11. system according to claim 1, wherein said network is the set by a plurality of elements (element) network of different tissues control,
The scope of the routing information of safeguarding in the network based path control between described element network of described element forms staging hierarchy,
The described media termination unit that at least one intercoms mutually is positioned at the top of this staging hierarchy, and is interconnected to the ground floor of the described element network of the routing information of preserving all the other element networks alone.
12. system according to claim 8, wherein said network is the set by a plurality of element networks of different tissues control,
The scope of the routing information of safeguarding in the network based path control between described element network of described element forms staging hierarchy,
The described media termination unit that at least one intercoms mutually is positioned at the top of this staging hierarchy, and is interconnected to the ground floor of the described element network of the routing information of preserving all the other element networks alone.
13. system according to claim 9, wherein said network is the set by a plurality of element networks of different tissues control,
The scope of the routing information of safeguarding in the network based path control between described element network of described element forms staging hierarchy,
The described media termination unit that at least one intercoms mutually is positioned at the top of this staging hierarchy, and is interconnected to the ground floor of the described element network of the routing information of preserving all the other element networks alone.
14. system according to claim 10, wherein said network is the set by a plurality of element networks of different tissues control,
The scope of the routing information of safeguarding in the network based path control between described element network of described element forms staging hierarchy,
The described media termination unit that at least one intercoms mutually is positioned at the top of this staging hierarchy, and is interconnected to the ground floor of the described element network of the routing information of preserving all the other element networks alone.
15. be interconnected to a kind of media terminal apparatus of network based on communications protocol, be used for will be relevant with first audio signal audio frequency media information be inserted into the data of the agreement relevant with this communication protocol, and on real-time basis be connected to a side communication of described equipment, comprising:
Information conversion circuit, be used for operating below real time communication is carried out at least one: first audio signal that receives based on the near-end from described equipment produces audio frequency media information by coding, recovers first audio signal with the audio frequency media information that provides based on a side who is connected from this; And
Interface circuit, be used to carry out at least one following operation: receive the first music data that provide from a side of this connection with a kind of data format, the first music data be converted to second audio signal and receive second music data to send this second music data from this near-end.
16. equipment according to claim 15 further comprises mixer, be used for by first audio signal recovering from audio frequency media information to obtain with mix by second audio signal of obtaining from music data conversion.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP400080/2003 | 2003-11-28 | ||
| JP2003400080A JP4389560B2 (en) | 2003-11-28 | 2003-11-28 | Real-time communication system and media end terminal |
Publications (2)
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| CN1622550A true CN1622550A (en) | 2005-06-01 |
| CN1622550B CN1622550B (en) | 2010-11-10 |
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| CN2004100958587A Expired - Fee Related CN1622550B (en) | 2003-11-28 | 2004-11-26 | Real-time communications system of high communications quality and media terminal apparatus |
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|---|---|
| US (1) | US7672296B2 (en) |
| JP (1) | JP4389560B2 (en) |
| CN (1) | CN1622550B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106328106A (en) * | 2016-11-09 | 2017-01-11 | 佛山市高明区子昊钢琴有限公司 | Multimediapiano and automatic playing method and system thereof |
| CN107770135A (en) * | 2016-08-19 | 2018-03-06 | 范子文 | The music live broadcasting method and device of electronic musical instrument |
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| US7511215B2 (en) * | 2005-06-15 | 2009-03-31 | At&T Intellectual Property L.L.P. | VoIP music conferencing system |
| US10297127B1 (en) * | 2017-12-18 | 2019-05-21 | Arris Enterprises Llc | Home security systems and Bluetooth Wi-Fi embedded set-tops and modems |
| US10825351B2 (en) * | 2018-10-24 | 2020-11-03 | Michael Grande | Virtual music lesson system and method of use |
| JP6986804B1 (en) * | 2021-09-15 | 2021-12-22 | 鉄太郎 中村 | Sports improvement support device and sports improvement support program |
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| JPH01293382A (en) | 1988-05-20 | 1989-11-27 | Fujitsu Ltd | Handwriting system with plural terminals |
| US5533112A (en) * | 1994-03-31 | 1996-07-02 | Intel Corporation | Volume control in digital teleconferencing |
| JPH10143456A (en) | 1996-11-15 | 1998-05-29 | Mitsubishi Electric Corp | Message system |
| US6785267B1 (en) * | 1999-01-04 | 2004-08-31 | Cisco Technology, Inc. | Access and control system for enhanced audio capabilities in an integrated telephony/high speed data access device |
| EP1168734A1 (en) * | 2000-06-26 | 2002-01-02 | BRITISH TELECOMMUNICATIONS public limited company | Method to reduce the distortion in a voice transmission over data networks |
| US6898637B2 (en) * | 2001-01-10 | 2005-05-24 | Agere Systems, Inc. | Distributed audio collaboration method and apparatus |
| US6660922B1 (en) * | 2001-02-15 | 2003-12-09 | Steve Roeder | System and method for creating, revising and providing a music lesson over a communications network |
| JP2002323849A (en) | 2001-04-25 | 2002-11-08 | Megafusion Corp | Remote music education system |
| JP3964159B2 (en) | 2001-06-25 | 2007-08-22 | 株式会社ノヴァ | Education service system using communication line and education service providing method |
| CN100418157C (en) * | 2001-07-03 | 2008-09-10 | 旭联科技股份有限公司 | Video-audio system |
| JP3738720B2 (en) | 2001-09-27 | 2006-01-25 | ヤマハ株式会社 | Information processing apparatus, control method therefor, control program, and recording medium |
| US6950119B2 (en) * | 2002-04-15 | 2005-09-27 | Sumitomo Electric Industries, Ltd. | Videoconference system, terminal equipment included therein and data delivery method |
| US20040207719A1 (en) * | 2003-04-15 | 2004-10-21 | Tervo Timo P. | Method and apparatus for exploiting video streaming services of mobile terminals via proximity connections |
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2003
- 2003-11-28 JP JP2003400080A patent/JP4389560B2/en not_active Expired - Fee Related
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- 2004-11-23 US US10/994,335 patent/US7672296B2/en not_active Expired - Fee Related
- 2004-11-26 CN CN2004100958587A patent/CN1622550B/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107770135A (en) * | 2016-08-19 | 2018-03-06 | 范子文 | The music live broadcasting method and device of electronic musical instrument |
| CN106328106A (en) * | 2016-11-09 | 2017-01-11 | 佛山市高明区子昊钢琴有限公司 | Multimediapiano and automatic playing method and system thereof |
Also Published As
| Publication number | Publication date |
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| JP4389560B2 (en) | 2009-12-24 |
| US20050117569A1 (en) | 2005-06-02 |
| CN1622550B (en) | 2010-11-10 |
| JP2005167362A (en) | 2005-06-23 |
| US7672296B2 (en) | 2010-03-02 |
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